Composite materials prepared by coating metal reinforcing materials such as steel cords with rubber compositions for the purpose of reinforcing rubbers to enhance strength and durability thereof have so far been used for rubber products to which strength is particularly required such as tires for cars, conveyor belts, hoses and the like.
Adhesion which is stable and less changed with the passage of time is required between the rubbers and the metal reinforcing materials in order to allow the above rubber-metal composite materials to exert a high reinforcing effect and obtain reliability.
Further, when rubber is adhered to metal, a method in which the rubber and the metal are bonded at the same time, that is, a direct vulcanization bonding method is known, and in this case, it is considered to be useful that a sulfeneamide base vulcanization accelerator which provides vulcanization reaction with delayed action is used when vulcanization of the rubber and bonding of the rubber and the metal are carried out at the same time.
At present, N,N-dicyclohexyl-2-benzothiazolylsulfeneamide (hereinafter abbreviated as “DCBS”) represented by the following formula is known as a vulcanization accelerator which provides vulcanization reaction with the largest delayed action among commercially available sulfeneamide base vulcanization accelerators:

Further, when a larger delayed action than that in vulcanization reaction of DCBS is required, a vulcanization retardant other than a sulfeneamide base vulcanization accelerator is used in combination. N-(cyclohexylthio)phthalimide (hereinafter abbreviated as “CTP”) is known as a representative vulcanization retardant which is commercially available, but it has already been known that if this CTP is compounded with rubber in a large amount, it exerts an adverse effect on the physical properties of the vulcanized rubber and that it causes blooming which deteriorates the appearance of the vulcanized rubber and exerts an adverse effect on an adhesive property thereof.
Further, bissulfeneamides represented by a specific formula (patent document 1) and benzothiazolylsulfeneamide base vulcanization accelerators (patent document 2) obtained by using amines originating in natural fats and oils as raw materials are known as sulfeneamide base vulcanization accelerators other than DCBS described above.
However, only rubber physical properties are described with respect to the sulfeneamide base vulcanization accelerators described in the patent documents 1 and 2, and the adhesion performances are neither described nor suggested therein. In addition thereto, it is neither described nor suggested at all that the sulfeneamide compound of the present invention can be used as a novel vulcanization accelerator for rubbers.
Further, several production processes for the sulfeneamide compounds used in the present invention are known in, for example, patent documents 3, 4 and 5, but it is neither described nor suggested at all that the above compounds can be used as a novel vulcanization accelerator for rubbers, and an adhesion performance with a steel cord which is brought by the above vulcanization accelerators is neither described nor suggested therein as well.    Patent document 1: Japanese Patent Application Laid-Open No. 139082/2005    Patent document 2: Japanese Patent Application Laid-Open No. 139239/2005    Patent document 3: EP0314663A1    Patent document 4: British Patent No. 1177790    Patent document 5: Japanese Examined Patent Application Publication Sho 48 No. 11214